Tesis previa a la obtención del Título de Ingeniero en Electrónica y ...

Multhrame
Sub-multi frame
(SMF)
SMF1
SMF2
SMF3
SMF4
SMF5
SMF6
SMF7
SMF8
Frame
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Channel number, least significan! bit in L1
Channel 13 L2 L1
Initial O O 1
Second
Third
Sixth 1 1 0
Reserved forfuture use set lo 0.
E, C1-C4 As in Figure 3.
1
N1 '
0
N2
0
N3
1
N4
0
N5
1
L1
1
L2
L3
TEA
R
2
. 0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
Bits 1 to 8 of the service channel in every frame
-N4 Used for multiframe numbering as descríbed in 2.2; set to O while numbering Ís inactive.
3
0
A
0
A
0
A
0
A
0
A
0
A
0
A
0
A
N4 N3 N2 N1
Uultiframe number 0 0 0 0 0 (or numbaring inactiva)
1 0 0 0 1
2 0 0 1 0
15 1 1 1 1
Indícales whether muliíframe numbering ¡s active (N5 = 1} or inactive (N5 = 0).
A The termina! equipment alarm ís set to 1 in the outgoing signa! while an internal terminal equipment fault exists such that it
cannot receíve and act on Ihe incoming signa!. Otherwise it Ís set to 0.
FIGURE 4/H.221
Assigntnent of bits 1-8 of the service channel in each frame in a multiframe
i Loss and recovery of frame alignment
irae alignment is defined to have been lost when three consecutive frame alignment words have been received with an
4
1
E
1
E
1
E
1
E
1
E
1
E
1
E
1
E
5
1
C1
1
C1
1
C1
1
C1
1
Cl
1
C1
1
C1
1
C1
6
0
C2
0
C2
0
C2
0
C2
0
C2
0
C2
0
C2
0
C2
Recommendation H.221 (03/93)
7
1
C3
1
C3
1
C3
1
C3
1
C3
1
C3
1
C3
1
C3
8
1
C4
1
C4
1
C4
1
C4
1
C4
1
C4
1
C4
1
C4